Abstract : Methods of plasma propulsion are discussed and a detailed exposition on a variation of the rail device (the coaxial accelerator) is presented. Parameters necessary for accelerating a metal derived plasma with an aggregate mass of one milligram to a velocity of 10 to the 8th power cm/sec are established. In a discussion of plasma diagnostics, the techniques of Langmuir probes, the Mach-Zehnder interferometer, spectroscopy, and photography are presented. The diagnostic techniques describe methods for obtaining plasma temperature and density primarily. (Author)